"We Christians have known about it for a very long time."
We UK citizens who did RE at school know it says "thou shalt not kill."
Christians say "thou shalt not kill." They used to put it on placards in the 1950s and stand outside prisons when people were being hanged, back in the days before civilising influences lifted us above barbaric practices.
When I pop up into the church ringing chamber from time to time to update the ringing educational software (abel) I walk past a poster with the commandments on. Guess what? It says "thou shalt not kill."